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Title: Characterisation of optically cleared paper by optical coherence tomography

Abstract

Due to the highly light scattering nature of paper, the imaging depth of optical methods such as optical coherence tomography (OCT) is limited. In this work, we study the effect of refractive index matching on improving the imaging depth of OCT in paper. To this end, four different refractive index matching liquids (ethanol, 1-pentanol, glycerol and benzyl alcohol) with a refraction index between 1.359 and 1.538 were used in experiments. Low coherent light transmission was studied in commercial copy paper sheets, and the results indicate that benzyl alcohol offers the best improvement in imaging depth, while also being sufficiently stable for the intended purpose. Constructed cross-sectional images demonstrate visually that the imaging depth of OCT is considerably improved by optical clearing. Both surfaces of paper sheets can be detected along with information about the sheet's inner structure. (laser applications and other topics in quantum electronics)

Authors:
; ; ; ;  [1]
  1. Department of Electrical and Information Engineering, Optoelectronics and Measurement Techniques Laboratory, University of Oulu (Finland)
Publication Date:
OSTI Identifier:
21456849
Resource Type:
Journal Article
Resource Relation:
Journal Name: Quantum Electronics (Woodbury, N.Y.); Journal Volume: 36; Journal Issue: 2; Other Information: DOI: 10.1070/QE2006v036n02ABEH013121
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BENZYL ALCOHOL; DEPTH; ETHANOL; GLYCEROL; IMAGES; LASERS; LIGHT SCATTERING; LIGHT TRANSMISSION; PENTANOLS; REFRACTION; REFRACTIVE INDEX; SHEETS; SURFACES; TOMOGRAPHY; ALCOHOLS; AROMATICS; DIAGNOSTIC TECHNIQUES; DIMENSIONS; HYDROXY COMPOUNDS; OPTICAL PROPERTIES; ORGANIC COMPOUNDS; PHYSICAL PROPERTIES; SCATTERING; TRANSMISSION

Citation Formats

Fabritius, T, Alarousu, E, Prykaeri, T, Hast, J, and Myllylae, Risto. Characterisation of optically cleared paper by optical coherence tomography. United States: N. p., 2006. Web. doi:10.1070/QE2006V036N02ABEH013121.
Fabritius, T, Alarousu, E, Prykaeri, T, Hast, J, & Myllylae, Risto. Characterisation of optically cleared paper by optical coherence tomography. United States. doi:10.1070/QE2006V036N02ABEH013121.
Fabritius, T, Alarousu, E, Prykaeri, T, Hast, J, and Myllylae, Risto. Tue . "Characterisation of optically cleared paper by optical coherence tomography". United States. doi:10.1070/QE2006V036N02ABEH013121.
@article{osti_21456849,
title = {Characterisation of optically cleared paper by optical coherence tomography},
author = {Fabritius, T and Alarousu, E and Prykaeri, T and Hast, J and Myllylae, Risto},
abstractNote = {Due to the highly light scattering nature of paper, the imaging depth of optical methods such as optical coherence tomography (OCT) is limited. In this work, we study the effect of refractive index matching on improving the imaging depth of OCT in paper. To this end, four different refractive index matching liquids (ethanol, 1-pentanol, glycerol and benzyl alcohol) with a refraction index between 1.359 and 1.538 were used in experiments. Low coherent light transmission was studied in commercial copy paper sheets, and the results indicate that benzyl alcohol offers the best improvement in imaging depth, while also being sufficiently stable for the intended purpose. Constructed cross-sectional images demonstrate visually that the imaging depth of OCT is considerably improved by optical clearing. Both surfaces of paper sheets can be detected along with information about the sheet's inner structure. (laser applications and other topics in quantum electronics)},
doi = {10.1070/QE2006V036N02ABEH013121},
journal = {Quantum Electronics (Woodbury, N.Y.)},
number = 2,
volume = 36,
place = {United States},
year = {Tue Feb 28 00:00:00 EST 2006},
month = {Tue Feb 28 00:00:00 EST 2006}
}
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  • Optical coherence tomography (OCT), based on a Michelson interferometer and utilizing low coherence light as the optical source, is a novel technique for the noninvasive imaging of optical scattering media. A simple OCT scheme based on a 3x3 fiber coupler is presented for the simultaneous measurement of the refractive index and thickness of optical samples. The proposed system enables the refractive index and thickness to be determined without any prior knowledge of the sample parameters and is characterized by a simple and compact configuration, a straightforward measurement procedure, and a low cost. The feasibility of the proposed approach is demonstratedmore » experimentally using BK7 and B270 optical glass samples.« less